• 제목/요약/키워드: point to point (P2P)

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청양-홍성간 도로에서의 강우 시 비점오염 유출특성 및 오염부하량 분석 (Runoff Characteristics and Non-point Source Pollution Loads from Cheongyang-Hongseong Road)

  • 이춘원;강선홍;안태웅;양주경
    • 상하수도학회지
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    • 제25권2호
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    • pp.265-274
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    • 2011
  • Nowadays, the importance of non-point source pollution treatment is being emphasized. Especially, the easy runoff characteristic of highly concentrated pollutants in the roads makes the circumstance more complicated due to impermeability of roads. When the pollutants flow into steam it could make water quality in stream worse and it also causes a bad influence in the aquatic ecosystem because the effluents of rainfall-runoff may contain indecomposable materials like oil and heavy metals. Therefore, we tried to figure out the property of non-point source pollution when it is raining and carried out an assessment for the property of runoff for non-point source pollution and EMC (Event Mean Concentrations) of the essential pollutants during this study. As the result of the study, the EMC was BOD 5.2~21.7 mg/L, COD 7.5~35.4 mg/L, TSS 71.5~466.1 mg/L, T-N 0.682~1.789 mg/L and T-P 0.174~0.378 mg/L, respectively. The decreasing rate of non-point pollutant in Chungyang-Hongsung road indicates the maximum decrease of 80% until 5 mm of rainfall based on SS concentration; by the rainy time within 20~30 minutes, the decreasing rate of SS concentration was shown as 88.0~97.6%. Therefore it was concluded that it seems to be possibly control non-point pollutants if we install equipments to treat non-point pollutants with holding capacity of 30 min. It is supposed that the result of this study could be used for non-point pollutants treatment of roads in Chungyang-Hongsung area. We also want to systematically study and consistently prepare the efficient management of runoff from non-point source pollution and pollutant loading because the characteristics of non-point source pollution runoff changes depending on different characteristics and situations of roads and rainfall.

京安川 流域의 土地利用에 따른 河川物質의 變化 (Changes in Stream Water Quality According to Land Use at Kyong-an Stream)

  • Yim, Yang-Jai;Bang, Je-Yong;Kim, Yoon-Dong
    • The Korean Journal of Ecology
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    • 제18권3호
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    • pp.341-351
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    • 1995
  • The relationship between land uses and water quality was investigated at Kyong-an Stream. Some 70% of this watershed was forested area, half of which was comprised of Pinus densilflora community. Concentrations of $NH_4^{+},\;NO_3^{-},\;NO_2^{-}, total nitrogen, $Cl^{-},\;PO_4^{3-}$, DO, and BOD increased gradually from upstream to downstream, whereas heavy metals did not have such tendancy with the exception of a few sites. Urban area was significantly correlated with hardness and chloride concentration. Relationship among phosphate concentration(P), cultivated field area(F), and stream length(S) in each basin was P = 1.7912 F/S+0.0103. the concentration of $NH_4^{+}$ was positively correlated with the population size and cow density within the catchment. The effect of urban area(U) and stream length of the pH(pH) was represented by pH = -4.7344 U/S+6.52. It can be concluded that the control of nonpoint source pollution as well as point source pollution is one of the important problems of water quality management, especially geological properties must be considered for sustainable development.

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조합식(組合式) 정백(精白)시스템의 설계(設計) 및 작동인자(作動因子)에 관(關)한 연구(硏究)(II) -작동기준(作動基準) 설정(設定)- (A Study on Design and Operational Factors of Rice Whitening Systems Consisting of Abrasive and Frictional Whiteners -Operational Criteria-)

  • 노상하;고학균;이종환;박승제
    • Journal of Biosystems Engineering
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    • 제12권2호
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    • pp.28-37
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    • 1987
  • Operation of rice whiteners has been depending on operator's experience only and very limitted data are available for operational criteria of rice whiteners in Korea. With developments of new rice varieties and with a tendency of automation of machine operations for precision control, operational criteria depending on physical characteristics of rice grains arc required for an improvement of milled rice recovery and the performance of rice whitening systems. An experimental study was conducted to identify operational criteria of a rice whitening system consisted with an abrasive-aerated whitener developed newly and a frictional-aerated whitener being used commercially. Further, comparisons were made between the performance of the rice whitening system adopted for this study and a commercial system used in small scale milling plants. Results of this study are summarized as follows: 1. Total number of passes necessary for the final white rice in the combined whitening system depended exclusively on the counter pressure level of the frictional whitener successive to the abrasive whitener. 2. The counter pressure required for whitening Japonica type rice variety (Akibare) was higher by about 1.6 times than that for Japonica type (Pung-san), when other conditions were kept at the same. 3. Radial pressure in the whitening chamber of the frictional whitener should be maintained between 1.5 to $2.1kg/cm^2$ for the completion of whitening within 5 to 3 passes regardless of rice varieties. Hence, it was found that the radial pressure in the whitening chamber could be used as an operational criteria to control the counter pressure level. 4. The following regression equation was found between radial pressure($R_p$) in whitening chamber and electric power consumption of the whitening system: $$EPC=-0.545\;R^2_p+1.277\;R_p+0.874[KWH/100kg]$$ 5. The following multiple regression equation was found among radial pressure ($R_p$), counter pressure ($C_p$), and bioyield point ($B_i$), length (L) and width (W) of brown rice. $$R_p/(B_i/W^2)=0.547\{C_p/(B_i/W^2)\}^{0.365}(L/W)^{0.120}(R^2=0.9897)$$ 6. The milled rice recovery and machine efficiency (kg/KWH) from the combined whitening system were higher by about 2.0% point and by 15 to 27% point than those from the conventional system, respectively.

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뉴메모리 기반 시스템에서 세밀한 COW 관리 기법을 통한 효율적 프로세스 체크포인팅 기법 (Efficient Process Checkpointing through Fine-Grained COW Management in New Memory based Systems)

  • 박재형;문영제;노삼혁
    • 정보과학회 논문지
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    • 제44권2호
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    • pp.132-138
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    • 2017
  • 본 연구에서는 뉴메모리 기반 컴퓨팅 시스템의 신뢰성을 높이기 위해 프로세스 단위로 체크포인팅하는 시스템을 설계하고 구현한다. 프로세스 체크포인팅을 위하여 일반적인 프로세스 실행에서 문맥전환이 일어나는 시점마다 결함이 발생하기 이전의 안전한 상태로 되돌아갈 수 있는 롤백 시점을 만든다. 본 연구에서는 롤백 시점의 안전한 프로세스 상태에 대한 새로운 프로세스를 만들며 이를 P-process(Persistent-process)라고 명명한다. P-process를 만드는 주기를 세밀한 간격인 문맥전환 때마다 만들기 때문에 결함이 발생하였을 때 롤백으로 인한 프로세스 실행시간 손실을 작게 만들 수 있다. P-process를 만드는 오버헤드를 줄이기 위하여 프로세스의 메모리 상태에서 변경된 부분만 저장할 수 있도록 COW(Copy-On-Write) 메커니즘을 이용하였다. 문맥전환 때마다 P-process를 생성하였을 때 PARSEC 벤치마크의 11개 워크로드 중 8개의 워크로드에서 5% 내의 실행 시간 오버헤드가 발생하였으며 오버헤드가 많이 발생한 워크로드도 P-process의 생성 주기의 조정으로 오버헤드를 감소시킬 수 있었다.

The Influence of Physical Therapy on the Changes in Clinical Dementia Rating Scale in Long-stay Elderly Patients

  • Kim, Ji Sung
    • 국제물리치료학회지
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    • 제5권1호
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    • pp.696-700
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    • 2014
  • This study was carried out to identify the influence of continuous physical therapy on long-stay elderly patients. This study classified 92 patients who had been hospitalized for one year into experimental group who continued to perform physical therapy and control group who did not conduct physical therapy and these two groups were classified into 0.5 point-questionable group, 1 point-mild dementia group, and 2 point-moderate dementia group based on the Clinical Dementia Rating Scale(CDR) when they were hospitalized in order to analyze the changes at the early stage of hospitalization and after one year has passed. As a result, it was appeared that both in CDR 0.5-point subgroup of questionable group and in CDR 1-point subgroup of mild dementia group, CDR was statistically significantly reduced in the experimental group whose physical therapy was continuously performed than in the control group whose physical therapy was not performed(p<.05) and that there was no significant difference in changes in the CDR between experimental group and control group in CDR 2-point group, which is a moderate dementia group.

POSITIVE SOLUTIONS OF NONLINEAR m-POINT BVP FOR AN INCREASING HOMEOMORPHISM AND POSITIVE HOMOMORPHISM ON TIME SCALES

  • Han, Wei;Jin, Zhen;Zhang, Guang
    • Journal of applied mathematics & informatics
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    • 제28권5_6호
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    • pp.1171-1184
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    • 2010
  • In this paper, by using fixed point theorems in cones, the existence of positive solutions is considered for nonlinear m-point boundary value problem for the following second-order dynamic equations on time scales $({\phi}(u^{\Delta}))^{\nabla}+a(t)f(t,\;u(t))=0$, t $\in$ (0, T), $u(0)=\sum\limits^{m-2}_{i=1}a_iu(\xi_i)$, $\phi(u^{\Delta}(T))=\sum\limits^{m-2}_{i=1}b_i{\phi}(u^{\Delta}(\xi_i))$, where $\phi$ : R $\rightarrow$ R is an increasing homeomorphism and positive homomorphism and ${\phi}(0)=0$. In [27], we obtained the existence results of the above problem for an increasing homeomorphism and positive homomorphism with sign changing nonlinearity. The purpose of this paper is to supplement with a result in the case when the nonlinear term f is nonnegative, and the most point we must point out for readers is that there is only the p-Laplacian case for increasing homeomorphism and positive homomorphism due to the sign restriction. As an application, one example to demonstrate our results are given.

Ultisol과 Alfisol 및 Inceptisol 토양에서 토양표면전하 측정에 사용된 이온흡착법, 전위차 적정법 및 역적정법간의 비교 (Comparison of the Ion Adsorption Method, Potentiometric Titraion and Backtitration Technique for Surface Charge measurement in Ultisol, Alfisol, and Inceptisol)

  • 이상은;;박준규;임수길
    • 한국토양비료학회지
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    • 제26권3호
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    • pp.160-171
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    • 1993
  • Ultisol(필리핀의 Luisiana 토양)과 Alfisol(필리핀의 Maahas 토양)및 Inceptisol(한국의 용지통) 토양의 표면전하 특성을 전위차 측정법과 역적정법 및 이온흡착법 등의 세가지 방법으로 정량하였고 분석법간의 차이를 비교한 결과는 아래와 같다. 1. 이온흡착법(또는 CEC-AEC method)으로 구한 PZNC(point of zero net charge)값은 Luisiana토양과 Maahas 토양 및 용지통에서 각각 3.1, 2.2 및 2.9였다. 따라서 이들 토양의 자연 pH조건에서는 음전하를 보였다. 2. 전위차 적정법과 역적정법에서 구한 PZSE(point of zero salt effect)값은 Maahas토양 외의 두 토양에서 일치하였다. 3. PZNC값은 PZSE값에 비해 모든 토양에서 낮았는데 이는 영구음전하의 영향으로 생각되었다. 한편 Uehara and gillman(1980)의 이론에 의해 구한 영구음전하는 Luisiana 토양과 Maahas 토양 및 용지통에서 각각 2.6, 4.5 및 0.4me/100g로 pH 7에서 측정된 CEC중 상당히 적은 부분을 차지하였다. 4. 역적정법은 pH가 너무 높거나 낮을 때 전위차 적정법이 표면전하를 과다 평가하는 결점을 보완해 주었으나 여전히 이온흡착법에 비해 과대 평가하고 있어 영구전하의 영향이 큰 보통 토양에서는 이온흡착법의 사용이 나을 것으로 판단되었다.

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The immediate effects of 830-nm low-level laser therapy on the myofascial trigger point of the upper trapezius muscle in visual display terminal workers: A randomized, double-blind, clinical trial

  • Lee, Jung-Hoon;Lee, Sun-Min
    • International Journal of Contents
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    • 제7권2호
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    • pp.59-63
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    • 2011
  • The aim of our study was to evaluate the immediate effects of an 830-nm Aluminium gallium arsenide (GaAlAs) laser, by examining the changes, in pressure-pain threshold (PPT) and tenderness at 3 kg of the myofascial trigger point (MTrP) of the upper trapezius muscle in visual display terminal (VDT) workers in comparison with placebo treatment. Thirty VDT workers (13 males, 17 females) with complaints of upper trapezius muscle were recruited. All participants were given either active GaAlAs laser (830 nm wavelength, 450 mW, 9 J at point) or placebo GaAlAs laser, according to the double-blinded and placebo-controlled trial. Both active and placebo low-level laser therapy (LLLT) treatments showed no significant effect on PPT and tenderness at 3 kg. These results suggest that a higher dosage may be necessary to produce immediate effects when applying LLLT to the MTrP of relatively large muscles such as the upper trapezius muscle.

일 지역 간호학과 학생과 의학전문대학원생간의 죽음에 대한 태도와 호스피스완화의료에 대한 인식비교 (The Differences of Attitude to Death and Perception on Hospice-Palliative Care between Nursing and Medical Students in an Area)

  • 김영선
    • 보건의료산업학회지
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    • 제7권2호
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    • pp.37-52
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    • 2013
  • The purpose of this study was to compare the differences of attitude to death and perception on HPC between nursing and medical students. The data was collected by questionnaires and the period of data collection was from September 17 to October 12, 2012. The results were as followings. Statistically significant differences were found course of knowing HPC(${\chi}^2$=24.29, p<.001), reason of unactive introduction(${\chi}^2$=15.92, p=.003), having to CPR in irresponsive terminal situation to you(${\chi}^2$=4.62, p=.032) and to your family(${\chi}^2$=5.64, p=.018), decision-making about DNR(${\chi}^2$=12.28, p=.002), awareness to medical authority legal representative(${\chi}^2$=14.75, p<.001), awareness (${\chi}^2$=11.01, p=.001) and subject(${\chi}^2$=24.73, p<.001) of AD, addiction(p<.001), tolerance(p<.001), taking a point(${\chi}^2$=23.28, p<.001) of narcotic analgesics and control of pain(p=.532). The findings of the study provides the basis for expanding practice and education to hospice-palliative care for nursing and medical students.

Comparison of the effects of transcutaneous electrical nerve stimulation, low level laser, and placebo treatment on temporomandibular joint disorders: a single-blind randomized controlled trial

  • Kim, Hyunjoong
    • Physical Therapy Rehabilitation Science
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    • 제9권4호
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    • pp.244-251
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    • 2020
  • Objective: Physical therapy techniques are required for patients with temporomandibular joint disorder (TMD), but the effects of treatment have not been compared. Therefore, effects of transcutaneous electrical nerve stimulation (TENS) and low level laser (LLL), which are most commonly used interventions, were compared. Design: Randomized controlled trial. Methods: Thirty-six participants with pain in the temporomandibular joint were enrolled, and 12 participants were randomly assigned to either the TENS group, LLL group, or placebo group. Each intervention was performed for a total of 6 sessions for 2 weeks. For the evaluation of the participants, the mouth opening (MO), pressure pain threshold (PPT), and stress were measured at three time periods: baseline, post-test, and follow-up at 2 weeks. Results: Significant interaction between groups according to each evaluation point was found only in PPT-masseter (p<0.05). The evaluation time point at which a significant difference appeared was at the post-test and follow-up at 2 weeks time periods. As a result of the post-test, the LLL group showed a significant improvement compared to the TENS group (p<0.05), and at 2 weeks follow-up, the TENS group showed a significant improvement compared to the placebo group (p<0.05). Conclusions: In this study, an experiment was conducted to compare the treatment effects when TENS, LLL, and placebo were given to patients with TMD. In addition, by quantitatively presenting the effect size of each treatment, this study suggests clinical use of TENS and LLL treatment for TMD.